The present invention relates to computer networks and more particularly to systems and methods for upgrading packet processing software without interfering with packet flow.
Routers are internetworking devices that are typically used to connect similar and heterogeneous network segments into internetworks. A typical router includes various interfaces that send and receive packets. The router receives a given packet through a first interface, processes the packet to determine how to best forward the packet to its destination, and then based on this determination transmits the packet through a selected second interface.
In a high speed data communication network, a router will handle a very large and continuous flow of packets. Any sustained interruption of router operation may adversely affect network performance due to increased latency or even loss of packets.
Many popular types of routers operate under the control of packet processing software. The packet processing software directly manipulates the individual packets to be forwarded by the router. As with any software controlled device, it is sometimes desirable or necessary to replace or upgrade the software. A problem arises in that changing software requires halting packet processing because it is the software that directly manipulates the packet. Systems and methods for replacing router software while minimizing impact on network operation are needed.